In U.S. Pat. Nos. 3,645,463 and 3,918,655, assigned to the assignee of the present invention, there is described an apparatus for automatically splicing the beginning of one roll of paper or the like onto the approximate end of a second roll of paper of like material without discontinuing the flow of paper to utilizing device.
The apparatus described in the U.S. Pat. No. 3,645,463 includes a support stand having means for supporting first and second rolls of paper in rotatable relationship therewith. Also carried on the support stand is a festooner arrangement including at least one set of displaceable rollers for establishing an elongated path of travel for paper of the exhausting roll, moving to the apparatus, and for allowing the utilizing device to feed upon the paper carried by the festooner when the second, exhausting roll of paper has stopped rotating to initiate the automatic splicing operation.
Once the exhausting roll of paper has stopped rotating and during the time that the displaceable rollers of the festooner are continually shortening the aforementioned elongated path of travel, such that the utilizing device still has a supply of paper upon which to feed; the clamping, severing and splicing assembly of the patented invention performs three functions. First, the clamping mechanism thereof clamps the paper of the exhausting roll between itself and a backing plate positioned on the opposite side of the path of travel of the paper. Second, and virtually immediately after the clamping operation, the severing portion of the clamping, severing and splicing assembly severs the exhausting roll of paper at a location beneath the position at which the trailing end of the exhausting roll is maintained by the clamp. Third, and virtually simultaneously with the aforedescribed severing, the splicing portion of the clamping, severing and splicing assembly joins the previously treated beginning end of a new roll of paper with the severed end of the exhausted roll of paper. Finally, once the clamping, severing and splicing assembly is reset, such that the clamping portion thereof is released from the trailing end of the exhausted roll of paper, the new roll of paper will begin to flow through the festooner rollers and onto the utilizing device.
As disclosed in U.S. Pat. No. 3,918,655, it has been found desirable to accelerate the new roll of paper to help it reach the speed of the utilizing device and thereby avoid the possibility of the paper being severed when the festooner supply is used up. To effectuate the acceleration of the new roll of paper, a motor is employed and controlled by a timer which energizes the motor for a predetermined period of time, selected in accordance with the weight of the roll of paper. A tension responsive mechanism is provided to sense the tension in the paper being dispensed from the new roll of paper and through the use of a variable potentiometer, to apply control signals to a braking mechanism associated with the shaft upon which the new roll of paper is supported. As the new roll of paper accelerates and its "pay out" of paper approaches the "take-up" of paper by the utilizing device, such equilibrium is sensed by the tension responsive mechanism so as to generate the necessary control signals to energize the braking mechanism and slow down the new roll of paper. Of course, any slow down of the new roll of paper will cause the tension responsive mechanism to generate appropriate control signals to deactivate the braking mechanism to allow the new roll of paper to speed up once again. In effect, the system functions as a servo-mechanism, allowing the new roll of paper to properly accelerate and decelerate in accordance with the speed of take-up of the utilizing device.
However, this apparatus did not eliminate the waste which occurs when the printed rolls are not spliced in the register. Typically, the user of printed material must either stop his production line to splice printed rolls together in register or he must splice out of register and scrap all production until the printing again lines up in proper order with his product.
Accordingly, it may be appreciated that a need for a fast and accurate web-splicing apparatus has long existed in the prior art.